1. Field of the Invention
The present invention relates to a photographing optical lens assembly, and more particularly, to a compact photographing optical lens assembly used in electronic devices.
2. Description of the Prior Art
In recent years, with the popularity of mobile phone cameras, the demand for compact imaging lenses is increasing, and the sensor of a general photographing camera is none other than CCD (charge coupled device) or CMOS device (Complementary Metal Oxide Semiconductor device). Furthermore, as advanced semiconductor manufacturing technology has allowed the pixel size of sensors to be reduced and the resolution of compact imaging lenses has gradually increased, there is an increasing demand for compact imaging lenses featuring better image quality.
A conventional compact photographing optical lens system, such as the one disclosed in U.S. Pat. No. 7,525,741, generally comprises two lens elements in order to reduce costs. However, the composition of two lens elements system has limited ability in correcting aberration, which is unable to satisfy the needs of high end imaging lens modules. On the other hand, when utilizing lens systems with more than two lens elements, the total track length of the lens assembly will be too long for the photographing optical lens system to stay compact.
In order to obtain high image quality while maintaining the feature of compactness, a photographing optical lens system comprising three lens elements becomes a viable solution, such as a three-lens-element photographing optical lens system disclosed in U.S. Pat. No. 7,443,613. This design has a bi-concave third lens element which easily increases the system sensitivity, and such arrangement will decrease the distance between the exit pupil and the image plane of the system, causing the incident angle of chief ray projecting onto the image plane to increase, which will reduce the amount of brightness surrounding the system and the image quality.
Therefore, a need exists in the art for a photographing optical lens system that features better image quality, maintains a moderate total track length and is applicable to compact portable electronic products.